Trailing Vettel by 13 points with three races remaining, Alonso knows his car's pace has to improve for him to have any chance of catching the two-time defending champion. The Spaniard finished a distant second to Vettel at the Indian GP last weekend. He had finished no better than third in the previous five races, and the commanding lead he held in the standings over the summer has quickly evaporated.

Kimi Raikkonen of Lotus is 67 points back in the standings in third spot, while Vettel's teammate Mark Webber is another six points behind.

"We believe and trust in our job and our team," said Alonso, who last week guaranteed Ferrari would still win the championship.

"We showed many times that we don't give up and we will fight until the end," he said. "When things become stressful when things become difficult, we can deliver 100 percent. The team has a lot of experience fighting for a world championships and everyone is very motivated."

Ferrari is actively trying to improve Alonso's car, and new parts are due in by Friday. Alonso said he doesn't expect those changes to close the gap immediately, but he said a more competitive car could put pressure on Red Bull and take advantage of any mistakes that Vettel makes.

"They had an easy four races, had a lot of margin and they can do little mistakes with no penalty," Alonso said. "We want to be so close to them to take the opportunity of everything they don't do perfect. We need to find perfection this weekend or these next three weekends."

Vettel is on the verge of clinching a third consecutive driver's championship. He can't do it this weekend, but a win would almost certainly allow him clinch the title at the United States Grand Prix later this month with a strong performance.

If so, he would join greats Juan Manuel Fangio and Michael Schumacher as the only drivers to win three championships in a row.

Vettel, who clinched the 2010 title in Abu Dhabi and then ran away with the title in 2011, has had a late resurgence after struggling early in the season with the car. He has won the past four races but knows that success can be fleeting.

After earning pole at last year's Abu Dhabi Grand Prix, he crashed on the opening lap due to a punctured tire. He also has retired twice this season with alternator failures.

Red Bull can clinch its third consecutive constructors' championship this weekend. It leads Ferrari by 91 points and McLaren by 101. That means Ferrari must score six points more than Red Bull to keep that race alive while McLaren need to score 15 points more.

While the drivers' trophy is effectively a two-man race, Raikkonnen has yet to give up. He acknowledged he was disappointed with his seventh-place finish in India and said he still felt the team could win a race. The Finn has had three second-place finishes and three third-places in his first year back in Formula One.

For his part, McLaren's Lewis Hamilton has shifted his attention to the constructors' championship now that he and his teammate Jenson Button are out of the title chase. Since announcing in September he would replace Michael Schumacher at Mercedes next year, Hamilton has not had a podium finish. But he said he remained committed to helping McLaren win the title.

Ferrari driver Fernando Alonso, of Spain, walks in the paddock at the Yas Marina racetrack in Abu Dhabi, United Arab Emirates on Thursday, Nov. 1. The Emirates Formula One Grand Prix will take place Sunday, Nov. 4.(AP)